Haskell Weekly News: November 14, 2006

Welcome to issue 49 of HWN, a weekly newsletter covering
developments in the Haskell community.

This week we see the announcement of a Haskell to Javascript compiler
project, and the overhaul of GHC's typeclass machinery is complete.

Announcements

Compiling Haskell to Javascript:
YCR2JS. Dimitry Golubovsky
announced
Ycr2js, a sub-project within the York Haskell Compiler (Yhc)
project. It is aimed to create a tool to convert an arbitrary Haskell
program into Javascript which in turn may be executed in any Web
browser. With great amount of help from the Yhc Team, the converter
has been integrated into the Yhc project, and initial stage of coding
and development has been completed. More
documentation.

System.FilePath 0.10. Neil Mitchell
announced
System.FilePath 0.10, which hopefully is pretty close to final. This
library manipulates FilePath's correctly on both Posix and
Windows.

Major typeclass overhaul. Simon Peyton-Jones
mentioned
that for some time he has been promising an overhaul of GHC's type
inference machinery to fix the interactions between type classes and
GADTs. This overhaul has now been completed, and user-visible changes
are summarised, including: GHC's type inference becomes complete, the
restriction that every constraint in a type signature must mention at
least one of the quantified type variables is lifted, dictionaries
are packaged in data constructors and the proper interaction between
GADTs and type classes is now respected.

Implementing the lambda calculus. Lennart Augustsson
wrote
about implementing interpreters for the lambda-calculus in Haskell,
to experiment
with different implementation methods.

Great language shootout: reloaded. Don Stewart
mentioned
that now GHC 6.6 is available on
the shootout machines, the time has come to improve the existing language shootout
entries. Improvements can be posted to the wiki
for review.

Jobs

Research position in spatial cognition
(Haskell-related). Till Mossakowski
announced
the availability of a Doctoral Research Assistant / Postdoctoral
Researcher position at the Universität Bremen, concerned with
classification and formalization of qualitative spatial calculi,
relations among these calculi, spatial ontologies, and route graphs.
More
information.

Code Watch

2006-11-06 21:27:30 GMT. Lennart Kolmodin. New
ghc-pkg option 'check'. A patch for ghc-pkg show broken packages (due to
missing dependencies) with a new command 'check', and also indicate broken
packages when using the command 'list'.

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